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from WHF's ground-water samples were biased on the high side, due to the presence of chromium adsorbed to suspended sediment in their ground-water samples. Levine•Fricke's recent investigation was designed to collect representative analytical data on dissolved total and hexavalent chrome in ground water samples collected from three downgradient monitoring wells and two upgradient (or background) wells. SCOPE OF INVESTIGATION Our scope of work consisted of ground-water sampling and laboratory analyses of the ground-water samples, as described below. Ground-Water Sampling Ground-water samples were collected from monitoring wells MW-5S, MW-7S, MW-10, MW-11, and MW-12 (Figure 2). Monitoring wells MW-7S and MW-5S are located up- gradient and/or outside the potentially affected area and were used to collect background ground-water samples. Wells MW-10, MW-11, and MW-12 are directly downgradient of the suspected brine release area. A centrifugal pump was used to remove three well volumes of water from each well prior to sampling. Water clarity, pH, temperature, specific conductance, and extracted water volume were monitored during the purging process to confirm that the purge water physical parameters were stable prior to sample collection. Ground-water samples were collected using a steam-cleaned Teflon bailer, and immediately transferred into plastic bottles for chromium and general minerals analyses. One 250 ml and two 500 ml plastic bottles were filled with the sampled ground water from each monitoring well. Field filtering was performed on the samples used for dissolved metals analyses (one 250 ml bottle and one 500 ml bottle from each well) using a 0.45 micron filter. The 250 ml sample (used for the hexavalent chromium analysis) was chilled and delivered to the analytical laboratory unpreserved within 8 hours of sampling for laboratory analysis within 24 hours of sampling. The unfiltered 500 ml sample was chilled and delivered to the laboratory unpreserved within 8 hours of sampling, for analysis on a normal turnaround basis. The field-filtered 500 ml sample (used for major ion and total chromium analyses) was preserved with nitric acid and delivered to the laboratory within 8 hours of sampling for analysis on a normal turnaround basis. 2